A small, tumid, smoothish, slightly inequilateral Yoldia, the anterior side rounded, the posterior somewhat produced, to which Y. (Sarepta) abyssicola, Smith*, from Station 246, Challenger Expedition, Mid North Pacific, at 2050 fathoms, and also Station 281, Mid South Pacific, at 2385 fathoms, seems somewhat allied. That species, however, appears more distinctly abbreviate posteriorly, and higher in proportion to its width. Y. ecaudata, Pelseneer,† may likewise be compared, a species which is closely akin to Y. abyssicola. This was obtained during the voyage of the Belgica in the Antarctic region, at a depth of 400-500 metres. Again, Y. Valettei, Lamy, from the South Orkneys, where an example was found in the stomach of a penguin, is much of the same outward form, but less than half the dimensions (2.2 × 1.65 × 1.5 mm.), and the teeth are only six in number on either side. The epidermis is likewise named as "flava" in contradistinction to "plumbea" or "olivacea."